1. Field of the Invention
This invention pertains to therapeutic cytoprotective-wound healing compositions and/or their metabolites useful for preventing and reducing injury to mammalian cells from cytotoxic agents. More particularly, the cytoprotective-wound healing compositions comprise a cytotoxic agent and a therapeutic wound healing composition.
A preferred embodiment of the therapeutic wound healing composition of this invention comprises (a) pyruvate selected from the group consisting of pyruvic acid, pharmaceutically acceptable salts of pyruvic acid, and mixtures thereof, (b) an antioxidant, and (c) a mixture of saturated and unsaturated fatty acids wherein the fatty acids are those fatty acids required for the repair of cellular membranes and resuscitation of mammalian cells. In another aspect of this invention the wound healing composition comprises (a) pyruvate selected from the group consisting of pyruvic acid, pharmaceutically acceptable salts of pyruvic acid, and mixtures thereof; and (b) an antioxidant.
2. Description of the Background
Wound Healing
Wounds are internal or external bodily injuries or lesions caused by physical means, such as mechanical, chemical viral, bacterial, or thermal means, which disrupt the normal continuity of structures. Such bodily injuries include contusions, wounds in which the skin is unbroken, incisions, wounds in which the skin is broken by a cutting instrument, and lacerations, wounds in which the skin is broken by a dull or blunt instrument. Wounds may be caused by accidents or by surgical procedures.
Wound healing consists of a series of processes whereby injured tissue is repaired, specialized tissue is regenerated, and new tissue is reorganized. Wound healing consists of three major phases: a) an inflammation phase (0-3 days), b) a cellular proliferation phase (3-12 days), and (c) a remodeling phase (3 days-6 months).
During the inflammation phase, platelet aggregation and clotting form a matrix which traps plasma proteins and blood cells to induce the influx of various types of cells. During the cellular proliferation phase, new connective or granulation tissue and blood vessels are formed. During the remodeling phase, granulation tissue is replaced by a network of collagen and elastin fibers leading to the formation of scar tissue.
When cells are injured or killed as a result of a wound, a wound healing step is desirable to resuscitate the injured cells and produce new cells to replace the dead cells. The healing process requires the reversal of cytotoxicity, the suppression of inflammation, and the stimulation of cellular viability and proliferation. Wounds require low levels of oxygen in the initial stages of healing to suppress oxidative damage and higher levels of oxygen in the later stages of healing to promote collagen formation by fibroblasts.
Mammalian cells are continuously exposed to activated oxygen species such as superoxide (O.sub.2 --), hydrogen peroxide (H.sub.2 O.sub.2), hydroxyl radical (OH.sup..), and singlet oxygen (.sup.1 O.sub.2). In vivo, these reactive oxygen intermediates are generated by cells in response to aerobic metabolism, catabolism of drugs and other xenobiotics, ultraviolet and x-ray radiation, and the respiratory burst of phagocytic cells (such as white blood cells) to kill invading bacteria such as those introduced through wounds. Hydrogen peroxide, for example, is produced during respiration of most living organisms especially by stressed and injured cells.
These active oxygen species can injure cells. An important example of such damage is lipid peroxidation which involves the oxidative degradation of unsaturated lipids. Lipid peroxidation is highly detrimental to membrane structure and function and can cause numerous cytopathological effects. Cells defend against lipid peroxidation by producing radical scavengers such as superoxide dismutase, catalase, and peroxidase. Injured cells have a decreased ability to produce radical scavengers. Excess hydrogen peroxide can react with DNA to cause backbone breakage, produce mutations, and alter and liberate bases. Hydrogen peroxide can also react with pyrimidines to open the 5,6-double bond, which reaction inhibits the ability of pyrimidines to hydrogen bond to complementary bases, Hallaender et al. (1971). Such oxidative biochemical injury can result in the loss of cellular membrane integrity, reduced enzyme activity, changes in transport kinetics, changes in membrane lipid content, and leakage of potassium ions, amino acids, and other cellular material.
Antioxidants have been shown to inhibit damage associated with active oxygen species. For example, pyruvate and other Alpha-ketoacids have been reported to react rapidly and stoichiometrically with hydrogen peroxide to protect cells from cytolytic effects, O'Donnell-Tormey et al., J. Exp. Med., 165, pp. 500-514 (1987).
U.S. Pat. Nos. 3,920,835, 3,984,556, and 3,988,470, all issued to Van Scott et al., disclose methods for treating acne, dandruff, and palmar keratosis, respectively, which consist of applying to the affected area a topical composition comprising from about 1% to about 20% of a lower aliphatic compound containing from two to six carbon atoms selected from the group consisting of Alpha-hydroxyacids, Alpha-ketoacids and esters thereof, and 3-hydroxybutryic acid in a pharmaceutically acceptable carrier. The aliphatic compounds include pyruvic acid and lactic acid.
U.S. Pat. Nos. 4,105,783 and 4,197,316, both issued to Yu et al., disclose a method and composition, respectively, for treating dry skin which consists of applying to the affected area a topical composition comprising from about 1% to about 20% of a compound selected from the group consisting of amides and ammonium salts of Alpha-hydroxyacids, .beta.-hydroxyacids, and Alpha-ketoacids in a pharmaceutically acceptable carrier. The compounds include the amides and ammonium salts of pyruvic acid and lactic acid.
U.S. Pat. No. 4,234,599, issued to Van Scott et al., discloses a method for treating actinic and nonactinic skin keratoses which consists of applying to the affected area a topical composition comprising an effective amount of a compound selected from the group consisting of Alpha-hydroxyacids, .beta.-hydroxyacids, and Alpha-ketoacids in a pharmaceutically acceptable carrier. The acidic compounds include pyruvic acid and lactic acid.
U.S. Pat. No. 4,294,852, issued to Wildnauer et al., discloses a composition for treating skin which comprises the Alpha-hydroxyacids, .beta.-hydroxyacids, and Alpha-ketoacids disclosed above by Van Scott et al. in combination with C.sub.3 -C.sub.8 aliphatic alcohols.
U.S. Pat. No. 4,663,166, issued to Veech, discloses an electrolyte solution which comprises a mixture of L-lactate and pyruvate in a ratio from 20:1 to 1:1, respectively, or a mixture of D-.beta.-hydroxybutyrate and acetoacetate, in a ratio from 6:1 to 0.5:1, respectively.
Sodium pyruvate has been reported to reduce the number of erosions, ulcers, and hemorrhages on the gastric mucosa in guinea pigs and rats caused by acetylsalicylic acid. The analgesic and antipyretic properties of acetylsalicylic acid were not impaired by sodium pyruvate, Puschmann, Arzneimittelforschung, 33, pp. 410-415 and 415-416 (1983).
Pyruvate has been reported to exert a positive inotropic effect in stunned myocardum, which is a prolonged ventricular dysfunction following brief periods of coronary artery occlusions which does not produce irreversible damage, Mentzer et al., Ann. Surg., 209, pp. 629-633 (1989).
Pyruvate has been reported to produce a relative stabilization of left ventricular pressure and work parameter and to reduce the size of infarctions. Pyruvate improves resumption of spontaneous beating of the heart and restoration of normal rates and pressure development, Bunger et al., J. Mol. Cell. Cardiol., 18, pp. 423-438 (1986), Mochizuki et al., J. Physiol. (Paris), 76, pp. 805-812 (1980), Regitz et al., Cardiovasc. Res., 15, pp. 652-658 (1981), Giannelli et al., Ann. Thorac. Surg., 21, pp. 386-396 (1976).
Sodium pyruvate has been reported to act as an antagonist to cyanide intoxication (presumably through the formation of a cyanohydrin) and to protect against the lethal effects of sodium sulfide and to retard the onset and development of functional, morphological, and biochemical measures of acrylamide neuropathy of axons, Schwartz et al., Toxicol. Appl. Pharmacol., 50, pp. 437-442 (1979), Sabri et al., Brain Res., 483, pp. 1-11 (1989).
A chemotherapeutic cure of advanced L1210 leukemia has been reported using sodium pyruvate to restore abnormally deformed red blood cells to normal. The deformed red blood cells prevented adequate drug delivery to tumor cells, Cohen, Cancer Chemother. Pharmacol., 5, pp. 175-179 (1981).
Primary cultures of heterotopic tracheal transplant exposed in vivo to 7,12-dimethyl-benz(a)anthracene were reported to be successfully maintained in enrichment medium supplemented with sodium pyruvate along with cultures of interleukin-2 stimulated peripheral blood lymphocytes, and plasmacytomas and hybridomas, pig embryos, and human blastocysts, Shacter, J. Immunol. Methods, 99, pp. 259-270 (1987), Marchok et al., Cancer Res., 37, pp. 1811-1821 (1977), Davis, J. Reprod. Fertil. Suppl., 33, pp. 115-124 (1985), Okamoto et al., No To Shinkei, 38, pp. 593-598 (1986), Cohen et al., J. In Vitro Fert. Embryo Transfer, 2, pp. 59-64 (1985).
U.S. Pat. Nos. 4,158,057, 4,351,835, 4,415,576, and 4,645,764, all issued to Stanko, disclose methods for preventing the accumulation of fat in the liver of a mammal due to the ingestion of alcohol, for controlling weight in a mammal, for inhibiting body fat while increasing protein concentration in a mammal, and for controlling the deposition of body fat in a living being, respectively. The methods comprise administering to the mammal a therapeutic mixture of pyruvate and dihydroxyacetone, and optionally riboflavin. U.S. Pat. No. 4,548,937, issued to Stanko, discloses a method for controlling the weight gain of a mammal which comprises administering to the mammal a therapeutically effective amount of pyruvate, and optionally riboflavin. U.S. Pat. No. 4,812,479, issued to Stanko, discloses a method for controlling the weight gain of a mammal which comprises administering to the mammal a therapeutically effective amount of dihydroxyacetone, and optionally riboflavin and pyruvate.
Rats fed a calcium-oxalate lithogenic diet including sodium pyruvate were reported to develop fewer urinary calculi (stones) than control rats not given sodium pyruvate, Ogawa et al., Hinyokika Kiyo, 32, pp. 1341-1347 (1986).
U.S. Pat. No. 4,521,375, issued to Houlsby, discloses a method for sterilizing surfaces which come into contact with living tissue. The method comprises sterilizing the surface with aqueous hydrogen peroxide and then neutralizing the surface with pyruvic acid.
U.S. Pat. No. 4,416,982, issued to Tauda et al., discloses a method for decomposing hydrogen peroxide by reacting the hydrogen peroxide with a phenol or aniline derivative in the presence of peroxidase.
U.S. Pat. No. 4,696,917, issued to Lindstrom et al., discloses an eye irrigation solution which comprises Eagle's Minimum Essential Medium with Earle's salts, chondroitin sulfate, a buffer solution, 2-mercaptoethanol, and a pyruvate. The irrigation solution may optionally contain ascorbic acid and Alpha-tocopherol. U.S. Pat. No. 4,725,586, issued to Lindstrom et al., discloses an irrigation solution which comprises a balanced salt solution, chondroitin sulfate, a buffer solution, 2-mercaptoethanol, sodium bicarbonate or dextrose, a pyruvate, a sodium phosphate buffer system, and cystine. The irrigation solution may optionally contain ascorbic acid and gamma-tocopherol.
U.S. Pat. No. 3,887,702 issued to Baldwin, discloses a composition for treating fingernails and toenails which consists essentially of soybean oil or sunflower oil in combination with Vitamin E.
U.S. Pat. No. 4,847,069, issued to Bissett et al., discloses a photoprotective composition comprising (a) a sorbohydroxamic acid, (b) an anti-inflammatory agent selected from steroidal anti-inflammatory agents and a natural anti-inflammatory agent, and (c) a topical carrier. Fatty acids may be present as an emollient. U.S. Pat. No. 4,847,071, issued to Bissett et al., discloses a photoprotective composition comprising (a) a tocopherol or tocopherol ester radical scavenger, (b) an anti-inflammatory agent selected from steroidal anti-inflammatory agents and a natural anti-inflammatory agent, and (c) a topical carrier. U.S. Pat. No. 4,847,072, issued to Bissett et al., discloses a topical composition comprising not more than 25% tocopherol sorbate in a topical carrier.
U.S. Pat. No. 4,533,637, issued to Yamane et al., discloses a culture medium which comprises a carbon source, a nucleic acid source precursor, amino acids, vitamins, minerals, a lipophilic nutrient, and serum albumin, and cyclodextrins. The lipophilic substances include unsaturated fatty acids and lipophilic vitamins such as Vitamin A, D, and E. Ascorbic acid may also be present.
United Kingdom patent application no. 2,196,348A, to Kovar et al., discloses a synthetic culture medium which comprises inorganic salts, monosaccharides, amino acids, vitamins, buffering agents, and optionally sodium pyruvate adding magnesium hydroxide or magnesium oxide to the emulsion. The oil phase may include chicken fat.
U.S. Pat. No. 4,284,630, issued to Yu et al., discloses a method for stabilizing a water-in-oil emulsion which comprises adding magnesium hydroxide or magnesium oxide to the emulsion. The oil phase may include chicken fat.
Preparation H.TM. has been reported to increase the rate of wound healing in artificially created rectal ulcers. The active ingredients in Preparation H.TM. are skin respiratory factor and shark liver oil, Subramanyam et al., Digestive Diseases and Sciences, 29, pp. 829-832 (1984).
The addition of sodium pyruvate to bacterial and yeast systems has been reported to inhibit hydrogen peroxide production, enhance growth, and protect the systems against the toxicity of reactive oxygen intermediates. The unsaturated fatty acids and saturated fatty acids contained within chicken fat enhanced membrane repair and reduced cytotoxicity. The antioxidants glutathione and thioglycollate reduced the injury induced by oxygen radical species, Martin, Ph.D. thesis, (1987-89).
U.S. Pat. No. 4,615,697, issued to Robinson, discloses a controlled release treatment composition comprising a treating agent and a bioadhesive agent comprising a water-swellable but water-insoluble, fibrous cross-linked carboxy-functional polymer.
European patent application no. 0410696A1, to Kellaway et al., discloses a mucoadhesive delivery system comprising a treating agent and a polyacrylic acid cross-linked with from about 1% to about 20% by weight of a polyhydroxy compound such as a sugar, cyclitol, or lower polyhydric alcohol.